On Tue, May 24, 2011 at 1:23 PM, Frederik Ramm <[email protected]> wrote:
> Hi, > > > On 05/24/11 12:04, Igor Brejc wrote: > >> Yes, but is it really? It's a storage format, you need a 3rd party >> driver to read it >> > > Same for anything that uses protocol buffers, or for shapefiles, isn't it? Not necessarily the same thing. Writing protobuf reader is still much easier than implementing something like http://www.sqlite.org/fileformat.html and http://www.sqlite.org/fileformat2.html > > and it's optimized for querying, not for storing high >> volume of data in an efficient manner. And it's a database without a >> standard schema. >> > > I think that's right (apart fro the "optimized for querying" part perhaps > because I think it is very much in the hands of whoever creates the > spatiallite file whether it is good for querying or not). Even without any indices included, the data is still organized for random access, which is not really necessary for a "transmission" file format. > > > I see spatialite as a good way for thick clients to store geo data >> without the need for an extra DB installation, but not as a good way to >> exchange data files (as opposed to osm.pbf, for example). >> > > Maybe I misunderstood. I thought that you had said "oh, shapefiles don't do > 64 bit IDs, maybe we should write a replacement for shapefiles then", and I > pointed out that such replacements IMHO already exist; I didn't claim that > they were a good OSM data transport format, and there's no reason to invent > a new OSM data transport format either IMHO. > I'm not talking about OSM-specific data transport format, just something that would: - not have an issue with 64bit IDs - be contained in a single file - be easy to read/write - use efficient binary storage tricks (like the ones PBF uses). >From reading what spatialite's author has to say on the subject, he finds spatialite format to be useful because of its inherent querying abilities but not as a transmission file format: https://groups.google.com/forum/#!topic/spatialite-users/a1dFsdGUA0A So I presume Geofabrik will switch to providing spatialite extracts instead of shapefiles once the 64bit switch becomes a reality? Igor
_______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
